Alcohol abuse and smoking alter inflammatory mediator production by pulmonary and systemic immune cells.

Alcohol use disorders (AUDs) and tobacco smoking are associated with an increased predisposition for community-acquired pneumonia and the acute respiratory distress syndrome. Mechanisms are incompletely established but may include alterations in response to pathogens by immune cells, including alveolar macrophages (AMs) and peripheral blood mononuclear cells (PBMCs). We sought to determine the relationship of AUDs and smoking to expression of IFNγ, IL-1β, IL-6, and TNFα by AMs and PBMCs from human subjects after stimulation with lipopolysaccharide (LPS) or lipoteichoic acid (LTA).

γδ T cells protect against LPS-induced lung injury.

γδ T lymphocytes are a unique T cell population with important anti-inflammatory capabilities. Their role in acute lung injury, however, is poorly understood but may provide significant insight into lung-protective mechanisms occurring after injury. In a murine model of lung injury, wild-type C57BL/6 and TCRδ(-/-) mice were exposed to Escherichia coli LPS, followed by analysis of γδ T cell and macrophage subsets.

Regulatory T cells modulate granulomatous inflammation in an HLA-DP2 transgenic murine model of beryllium-induced disease.

Susceptibility to chronic beryllium disease (CBD) is linked to certain HLA-DP molecules, including HLA-DP2. To elucidate the molecular basis of this association, we exposed mice transgenic (Tg) for HLA-DP2 to beryllium oxide (BeO) via oropharyngeal aspiration. As opposed to WT mice, BeO-exposed HLA-DP2 Tg mice developed mononuclear infiltrates in a peribronchovascular distribution that were composed of CD4(+) T cells and included regulatory T (Treg) cells.

Complement activation and toll-like receptor-2 signaling contribute to cytokine production after renal ischemia/reperfusion.

The innate immune system causes tissue inflammation and injury after renal ischemia/reperfusion (I/R). The complement system is activated on ischemic tubular epithelial cells (TECs) and induces the cells to produce pro-inflammatory chemokines. TECs also express toll-like receptors (TLRs)-2 and -4.

Brief report: airways abnormalities and rheumatoid arthritis-related autoantibodies in subjects without arthritis: early injury or initiating site of autoimmunity?

Objective: To evaluate the presence of pulmonary abnormalities in rheumatoid arthritis (RA)-related autoantibody-positive subjects without inflammatory arthritis.

Methods: Forty-two subjects who did not have inflammatory arthritis but were positive for anti-cyclic citrullinated peptide antibodies and/or ≥2 rheumatoid factor isotypes (a profile that is 96% specific for RA), 15 autoantibody-negative controls, and 12 patients with established seropositive early RA (<1-year duration) underwent spirometry and high-resolution computed tomography (HRCT) lung imaging.

Results: The median age of autoantibody-positive subjects was 54 years, 52% were female, and 38% were ever-smokers; these characteristics were not significantly different from those of autoantibody-negative control subjects.

γδ T cells protect against lung fibrosis via IL-22.

Inflammation-induced pulmonary fibrosis (PF) leads to irreversible loss of lung function and is a predictor of mortality in numerous lung diseases. Why some subjects with lung inflammation but not others develop PF is unclear. In a mouse model of hypersensitivity pneumonitis that progresses to lung fibrosis upon repeated exposure to the ubiquitous microorganism Bacillus subtilis, γδ T cells expand in the lung and inhibit collagen deposition.

Gammadelta T cells and Th17 cytokines in hypersensitivity pneumonitis and lung fibrosis.

Hypersensitivity pneumonitis (HP) is an inflammatory lung disease caused by the repeated inhalation of aerosolized antigens. With chronic exposure to an inhaled antigen, patients are at risk of developing irreversible pulmonary fibrosis as well as an increased morbidity and mortality. Although alphabeta T cells have been shown to be important in the pathogenesis of HP, gammadelta T cells also accumulate in the bronchoalveolar lavage of patients with HP.

IL-17A-expressing T cells are essential for bacterial clearance in a murine model of hypersensitivity pneumonitis.

Hypersensitivity pneumonitis (HP) is an inflammatory lung disease characterized by a diffuse mononuclear cell infiltrate in the lung that can progress to pulmonary fibrosis with chronic exposure to an inhaled Ag. We previously reported that C57BL/6 mice repeatedly exposed to the ubiquitous microorganism Bacillus subtilis develop mononuclear infiltrates in the lung that contain Vgamma6/Vdelta1(+) gammadelta T cells. In the absence of this T cell subset, mice treated with B.

Role of γδ T Cells in Lung Inflammation.

The resident population of γδ T cells in the normal lung is small but during lung inflammation, γδ T cells can increase dramatically. Histological analysis reveals diverse interactions between γδ T cells and other pulmonary leukocytes. Studies in animal models show that γδ T cells play a role in allergic lung inflammation where they can protect normal lung function, that they also are capable of resolving infection-induced pulmonary inflammation, and that they can help preventing pulmonary fibrosis.

Th17-polarized immune response in a murine model of hypersensitivity pneumonitis and lung fibrosis.

Hypersensitivity pneumonitis is an environmental lung disease characterized by a diffuse mononuclear cell infiltrate in the lung that can progress to pulmonary fibrosis with chronic exposure to an inhaled Ag. Using a well-established murine model of hypersensitivity pneumonitis, we repeatedly exposed C57BL/6 mice to Saccharopolyspora rectivirgula to investigate whether T cells are required for lung fibrosis. In the absence of alphabeta T cells, TCRbeta(-/-) mice exposed to S.

The nonoperative treatment of acute, isolated (partial or complete) posterior cruciate ligament-deficient knees: an intermediate-term follow-up study.

Fifty-seven consecutive patients (58 knees) with an acute, isolated, posterior cruciate ligament (PCL) injury were treated nonoperatively. Clinical, radiographic, and functional assessment was performed at a mean follow-up of 6.9 years (range 2 to 19.

gammadelta T cells: an important source of IL-17.

IL-17 is a cytokine that plays an important role in orchestrating innate immune function. In addition, IL-17 has been shown to exacerbate autoimmune diseases. CD4(+) alphabeta T cells, gammadelta T cells, and NK cells all produce IL-17.

Reproductive hormone effects on strength of the rat anterior cruciate ligament.

The material properties of the anterior cruciate ligament (ACL) in female rats with normal estrous cycles were compared to those regulated by oral contraceptive steroids. Forty female Sprague-Dawley rats were divided into two groups: an experimental group received daily ethinylestradiol and levonorgestrel in a dosing model designed to simulate a typical oral contraception regime in humans, while a control group received daily oral placebo. After eight cycles, six rats from each group underwent daily phlebotomy to measure serum estradiol and progesterone levels over the course of a single 5-day estrous cycle.

Regulatory role of gammadelta T cells in the recruitment of CD4+ and CD8+ T cells to lung and subsequent pulmonary fibrosis.

The mechanisms by which T cells accumulate in the lungs of patients with pulmonary fibrosis are poorly understood. Because the lung is continually exposed to microbial agents from the environment, we repeatedly exposed C57BL/6 mice to the ubiquitous microorganism, Bacillus subtilis, to determine whether chronic exposure to an inhaled microorganism could lead to T cell accumulation in the lungs and subsequent pulmonary fibrosis. C57BL/6 mice repeatedly treated with B.

Oligoclonal CD4+ T cells in the lungs of patients with severe emphysema.

Rationale: Within the lungs of patients with severe emphysema, inflammation continues despite smoking cessation. Foci of T lymphocytes in the small airways of patients with emphysema have been associated with disease severity. Whether these T cells play an important role in this continued inflammatory response is unknown.

Effects of small incongruities in a sheep model of osteochondral autografting.

Background: Exact reconstruction of an osteochondral defect by autogenous transplantation (mosaicplasty) is difficult given the variation in joint surface contour. Clinical and experimental studies do not show the extent to which incongruity can be tolerated in autografting.

Hypothesis: Grafted articular cartilage will hypertrophy to correct the incongruity created by recession of the transplanted surface.

Timeline of tibial tunnel expansion after single-incision hamstring anterior cruciate ligament reconstruction.

Purpose: The purpose of this study was to determine the time frame for tibial tunnel expansion in patients undergoing anterior cruciate ligament (ACL) reconstruction with hamstring autografts using an endoscopic technique. Does this expansion occur immediately after surgery or over the first 12 weeks of rehabilitation?

Type Of Study: Observational study involving 10 patients.

Methods: The single incision technique used a transtibial approach for drilling the femoral tunnel.

Broken poly-L-lactic acid interference screw after ligament reconstruction.

The interference screw is a reliable method used to secure tendon to bone and bone to bone in ligament reconstruction. Historically, metal interference screws have been used for this purpose in both anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) reconstruction. However, several problems associated with the use of metal interference screws have led to the increasing use of bioabsorbable implants.

Response of hamstring and patellar tendon grafts for anterior cruciate ligament reconstruction during cyclic tensile loading.

The efficacy of anterior cruciate ligament (ACL) reconstruction in the knee using hamstring tendon or patellar tendon grafts is thought to depend on the relative amounts of graft elongation, or creep, following postoperative rehabilitation. In this study, the creep responses of the tendinous portions of these two graft types were compared during 1 hour of cyclic loading to 200 N at 1 Hz. In the hamstring tendon grafts, strains were measured in both the tissue and in the length-augmentation tape to identify the relative contribution of this particular graft fixation to overall creep.

Biodegradable interference screw augmentation reduces tunnel expansion after ACL reconstruction.

This study assessed 40 patients who underwent anterior cruciate ligament reconstruction with hamstring autografts using our standard technique. Twenty patients underwent tibial fixation augmentation with a biodegradable interference screw, and the remaining 20 patients did not. Patient groups were compared using radiographic evaluation of bone tunnel diameter, physical examination, and arthrometer measurements.

Arthroscopic localization of medial collateral ligament injury: Report of 2 cases in adults.

Injury to the medial collateral ligament has previously been assessed primarily using the clinical examination and magnetic resonance imaging. In this article, we describe an adjunct to these diagnostic tools: an arthroscopic observation to assess the specific location of the medial collateral ligament injury.